High level validation of JSON schema

It would be nice to have some sanity check for the JSON schema + ui:schema, for example the required fields consistency... Otherwise we have to go to the create record form to see the errors.
Maybe a _preview panel_ would help ?

No files or tests are named. Start by reproducing the JSON schema and ui:schema errors in the create record form, then inspect how those schemas are loaded and validated. Done should include an agreed high-level validation or preview behavior that exposes required-field inconsistencies before record creation.

Written by the indexing model from the issue text.